The proposals, in Senate legislation that could be introduced as early as today, would broaden the focus of the government's cybersecurity efforts to include not only military networks but also private systems that control essentials such as electricity and water distribution. At the same time, the bill would add regulatory teeth to ensure industry compliance with the rules, congressional officials familiar with the plan said yesterday.

Addressing what intelligence officials describe as a gaping vulnerability, the legislation also calls for the appointment of a White House cybersecurity "czar" with unprecedented authority to shut down computer networks, including private ones, if a cyberattack is underway, the officials said.

How industry groups will respond is unclear. Jim Dempsey, vice president for public policy at the Center for Democracy and Technology, which represents private companies and civil liberties advocates, said that mandatory standards have long been the "third rail of cybersecurity policy." Dempsey said regulation could also stifle creativity by forcing companies to adopt a uniform approach.

The legislation, co-sponsored by Senate Commerce Committee Chairman John D. Rockefeller IV (D-W.Va.) and Sen. Olympia J. Snowe (R-Maine), was drafted with White House input. Although the White House indicated it supported some key concepts of the bill, there has been no official endorsement.

Many of the proposals were based on recommendations of a landmark study last year by the Center for Strategic and International Studies.

Currently, government responsibility for cybersecurity is split: The Pentagon and the National Security Agency safeguard military networks, while the Department of Homeland Security provides assistance to private networks. Previous cybersecurity initiatives have largely concentrated on reducing the vulnerability of government and military computers to hackers.

A 60-day federal review of the nation's defenses against computer-based attacks is underway, and the administration has signaled its intention to incorporate private industry into those defenses in an unprecedented way.

"People say this is a military or intelligence concern, but it's a lot more than that," Rockefeller, a former intelligence committee chairman, said in an interview. "It suddenly gets into the realm of traffic lights and rail networks and water and electricity."

U.S. intelligence officials have warned that a sustained attack on private computer networks could cause widespread social and economic havoc, possibly shutting down or compromising systems used by banks, utilities, transportation companies and others.

The Rockefeller-Snowe measure would create the Office of the National Cybersecurity Adviser, whose leader would report directly to the president and would coordinate defense efforts across government agencies. It would require the National Institute of Standards and Technology to establish "measurable and auditable cybersecurity standards" that would apply to private companies as well as the government. It also would require licensing and certification of cybersecurity professionals.

The proposal would also mandate an ongoing, quadrennial review of the nation's cyberdefenses. "It's not a problem that will ever be completely solved," Rockefeller said. "You have to keep making higher walls."

Last week, Director of National Intelligence Dennis C. Blair told reporters that one agency should oversee cybersecurity for government and for the private sector. He added that the NSA should be central to the effort.

"The taxpayers of this country have spent enormous sums developing a world-class capability at the National Security Agency on cyber," he said.

Blair acknowledged there will be privacy concerns about centralizing cybersecurity, and he said the program should be designed in a way that gives Americans confidence that it is "not being used to gather private information."